End construction for bellows type envelopes and the like

ABSTRACT

An end construction for a bellows type envelope that is particularly designed to be manufactured on automatic machinery, in which each side wall of the envelope has at its base angle, an isosceles triangle-shaped area defined by fold lines; the isosceles triangle-shaped area is folded inwardly on the altitude of the triangle, with the apex of the triangle coincident with the intersection of the planes defined by the side wall and the bottom wall of the envelope; the equal parts of the triangle on opposite sides of the altitude are secured together.

United States Patent 1 [111 assarsa Dworkin .Ban. 14, 1975 END CONSTRUCTION FOR BELLOWS Primary Examiner-William 1. Price TYPE ENVELOPES AND THE LIKE [76] Inventor: Howard S. Dworkin, 26 Coventry Rd., Livingston, NJ. 07039 [22] Filed: Dec. 28, 1967 [21] Appl. No.: 694,141

[52] US. Cl 229/61, 229/68, 229/75 [51] Int. Cl B65d 33/00 [58] Field of Search 229/75, 61, 68

[56] References Cited UNITED STATES PATENTS 227,147 5/1880 Campbell 229/61 2,203,726 6/1940 Hellema 229/6l 2,945,617 7/1960 Normandin 229/68 3,063,6l8 11/1962 Berkowitz 229/68 Assistant Examiner-Stephen P. Garbe Attorney, Agent, or Firm-Blum, Moscovitz, Friedman & Kaplan [57] ABSTRACT An end construction for a bellows type envelope that is particularly designed to be manufactured on automatic machinery, in which each side wall of the envelope has at its base angle, an isosceles triangle-shaped area defined by fold lines; the isosceles triangleshaped area is folded inwardly on the altitude of the triangle, with the apex of the triangle coincident with the intersection of the planes defined by the side wall and the bottom wall of the envelope; the equal parts of the triangle on opposite sides of the altitude are secured together.

10 Claims, 4 Drawing Figures PAIENIED JAN 1 M975 I N VENTOR. HOWARD 5. DWORK/N mmw A TTORNEYS END CONSTRUCTION FOR BELLOWS TYPE ENVELOPES AND THE LIKE SUMMARY OF THE INVENTION Bellows type envelopes are well known and are particularly useful in modern commercial practice to contain large quantities of material, and must be capable of expanding to accept additions to the material accumulated therein. Numerous constructions have been adopted: for the purpose of making such envelopes capable of expanding to receive large amounts of material; for the purpose of making them durable; and for the purpose of improving their hinging action. Such envelopes have reached a high degree of expandability and durability, but they are costly to manufacture because of the numerous manual operations required. Automatic machinery is available for making less complex forms of envelopes, but none is available for making the conventional bellows type envelope that has great expandability and durability.

It has been found that durable, expandable, bellowstype envelopes may be designed, which nevertheless can be constructed upon automatic machinery. The present invention is directed toward that end. Thus, it is an object of this invention to provide a bellows type envelope with an end construction, which may be made on automatic machinery, eliminating manual folding and manual gluing.

It is another object of the invention to provide an end construction for bellows type envelopes which provides for liberal expansion.

Yet another object of the invention is to provide an end construction for bellows type envelopes which will be strong and durable, resistant to tearing or deterioration with repeated use.

A still further object of the invention is to provide an end construction for bellows type envelopes in which, upon expansion of the envelope, the side walls and the bottom wall will fall into proper position.

These objects and advantages as well as other objects and advantages may be attained by the construction shown by way of illustration in the drawings in which FIG. 1 is a plan view of an unfolded blank for a bellows type envelope;

FIG. 2 is a plan view of the partially folded blank shown in FIG. 1;

FIG. 3 is an external perspective view of an end of the completely folded and glued blank shown in FIGS. 1

and 2; and

FIG. 4 is an internal perspective view of the end of the completely folded and glued blank looking in the direction of the arrows, as shown in FIG. 3.

DETAILED DESCRIPTION Referring now to the drawings in detail, the present invention may be embodied in an end construction for a bellows type envelope, or in an expandable pocket, or even in such diverse objects as vacuum cleaner bags, merchandise bags, and similar containers. The bellows envelope is formed from a blank having an inward and outward surface, the blank being defined by inward and outward fold lines. An inwardfold line refers to a folding of the blank toward the inward surface and an outward fold line refers to a folding of the blank'toward the outward surface. A first latitudinal inward fold l1 defines the bottom edge of the front portion 12 of the envelope. A second latitudinal inward fold l3 defines the bottom edge of the back portion 14 of the envelope. Between the first latitudinal fold 11 and the second latitudinal fold 13 there is an area defining the bottom 15 of the envelope. The bottom 15 is divided into two generally equal halves by a median or bellows fold 16, which is a third but outward latitudinal fold. This fold line 16 bends outwardly to provide for the telescoping of the envelope. Along the sides of the sheet 10, there is an inward longitudinal or fourth fold line 17 on each side. This fold line v17 defines a longitudinal flap 18 which extends outwardly from the front 12 and the back. The flaps 18,18 define the side walls of the envelope. The flap 18 is folded over (see FIG. 2) onto the front 12 and the back 14 along the inward longitudinal fold line 17, and in this position, has an inner edge 19. On the folded over flap 18 there are two isosceles triangles 20,20 formed by inward fold lines. These triangles 20 have the base 21 of the triangle disposed along the inner edge 19 of the flap 18. The altitudes 22 of the triangles 20,20 are coincident respectively (i.e. astride) with the first latitudinal fold line 11 and the second latitudinal fold line 13. The apex 23 of each of the triangles 20 is coincident with the fourth or inward longitudinal fold line 17. The outer surface of each of the triangles 20,20 is provided with surface gum or adhesive and the opposing halves of the triangles 20,20 on opposite sides of the altitudes 22,22 are adhesively secured together.

Along the edge of the side-wall flap 18, there is a latitudinal extension 24 defined by an outward longitudinal fold line which is adhesively secured to the back of the flap 18 by having the glue applied to the inner surface thereof. This latitudinal extension 24 commences at the base angle 25 of one of the triangles 20 and extends along the edge of the side-wall flap 18. This construction provides an end construction for bellows type envelopes which may be completely folded, erected, and glued upon automatic machinery, effecting thereby great economy.

The foregoing description is merely intended to illustrate an embodiment of the invention. The component parts have been shown and described. They each may have substitutes which may perform a substantially similar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention; these substitutes are contemplated as being within the scope of the appended claims, although they are not specifically catalogued herein.

What is claimed is:

1. An end construction for a bellows-type envelope comprising a sheet having an outward and inward surface, a front wall, a bottom wall, and a back wall defined by first inward fold lines on a sheet, side walls defined by second inward fold lines on a sheet, said side walls defining a continuous longitudinal flap on both sides of the front wall, bottom wall and back wall, isosceles triangles defined by third inward fold lines on the side walls, the third inward fold lines being astride the first inward fold lines, and latitudinal extensions coextensive with a portion of each flap and defined by outward longitudinal fold lines, the flaps being folded over respective front, bottom and back walls, the front and back wall folded Over in registration with each other and the bottom wall folded outwardly upon itself, the opposing faces on the Outward side of each of the triangles being folded together and secured together, the

I latitudinal extension being secured to said continuous flaps at portions not coextensive with said latitudinal extensions.

2. The end construction according to claim 1, and a medial outward latitudinal fold line on the bottom wall;

3. An end construction for a bellows type envelope comprising a sheet having an inward and outward side, three latitudinal fold lines on the sheet, the first and third being inward fold lines defining between them, a bottom for the envelope, and said inward latitudinal fold lines further defining the front and back of the envelope; and the second fold line being an outward fold line definingan outwardly bending fold in the center of the bottom of the envelope, a longitudinal inward fold on each side edge of the sheet extending the length of said sheet, said inward folds defining flaps constituting expandable side walls for the envelope, isosceles triangular areas defined by inward fold lines, each on opposite sides of the second latitudinal fold line, each triangle having an altitude in registration with one of the longitudinal fold lines, each triangle having a base lying on an edge of the flap and a base angle of each triangle terminating on the middle latitudinal fold line at the edge-of the flap, each half of one isosceles triangle on one side of the triangles altitude being attached to the opposite half thereof on the other side of the altitude, whereby when the expandable end wall is disposed with the portions on either side of the middle latitudinal fold, in the same plane, the side walls will be extended generally perpendicular to the front and back portions, a latitudinal extension on a portion of the flaps defined by outward longitudinal fold lines, the extensions being attached to the corresponding opposite portion of the flaps.

4. An expansible envelope comprising: a one piece blank including a substantially rectangular front panel, a back panel coextensive with and hingedly depending from the lower edge of said front panel by inboard and outboard bottom gusset panels defined by transversely extending triple score lines, an inboard gusset panel hinged to each of the lateral edges of said front panel along corresponding inboard longitudinally extending score lines, a gusset section coextensive with and hinged to each of the lateral edges of said back panel alongan extension of the corresponding inboard longitudinally extending score line, said inboard and outboard bottom gusset panels, said inboard side gusset panels and said gusset sections all being substantially equal in width along a dimension perpendicular to the respective hinged score lines thereof, a flap substantially coextensive with and hinged to the lower edge of each of said inboard side gusset panels along extensions of the inboard transverse score line and being further hinged to each of the lateral edges of said inboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, a tab substantially coextensive with and hinged to the adjacent edge of each of said gusset sections along extensions of the outboard transverse score line and being further hinged to each of the lateral edges of said outboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, said flaps and said tabs being respectively hinged to each other along extensions of the intermediate transverse score line, a top sealing flap hinged to the upper edge of said front panel, and an outboard side gusset panel hinged to the lateral edge of each of said inboard side gusset panels along a corresponding outboard longitudinally extending score line and having a lower edge terminating at a position short of the inboard transverse score line by a space substantially equal to the width of one of said gusset panels to define a clearance below said outboard side gusset panels, said inboard side gusset panels, said flaps, said tabs and said gusset sections being inwardly folded along the corresponding inboard longitudinally extending score line, said outboard side gusset panels being then outwardly folded along the corresponding outboard longitudinally extending score line, said bottom gusset panels and said back panel being inwardly, outwardly and then inwardly folded along the transverse triple score lines, and said gusset sections being adhesively secured to the corresponding underlying outboard gusset panels and portions of said flaps and tabs being adhesively secured to each other whereby all gussets are interiorly folded with closed corners.

5. An expansible envelope comprising a one piece blank including a substantially rectangular front panel, a back panel coextensive with and hingedly depending from the lower edge of said front panel by inboard and outboard bottom gusset panels defined by transversely extending triple score lines, an inboard side gusset panel hinged to each of the lateral edges of said front panel along corresponding inboard longitudinally extending score lines, a gusset section coextensive with and hinged to each of the lateral edges of said back panel along an extension of the corresponding inboard longitudinally extending score line,'said inboard and outboard bottom gusset panels, said inboard side gusset panels and said gusset sections all being substantially equal in width along a dimension perpendicular to the respective hinged score lines thereof, a flap substantially coextensive with and hinged to the lower edge of each of said inboard side gusset panels along extensions of the inboard transverse score line and being further hinged to each of the lateral edges of said inboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, a tab substantially coextensive with and hinged to the adjacent edge of each of said gusset sections along extensions of the outboard transverse score .line and being further hinged to each of thelateral edges of said outboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, said flaps and said tabs being respectively hinged to each other along extensions of the intermediate transverse score line, and an outboard side gusset panel hinged to the lateral edge of said inboard side gusset panels along a corresponding outboard longitudinally extending score line and having a lower edge terminating at a position short of the inboard transverse score line by a space substantially equal to the width of one of said gusset panels to define a clearance below said outboard side gusset panels, said inboard side gusset panels, said flaps, said tabs and said gusset sections being inwardly folded along the corresponding inboard longitudinally extending score line, said outboard side gusset panels being then outwardly folded along the corresponding outboard longitudinally extending score line, said bottom gusset panels and said back panel being inwardly, outwardly and then inwardly folded along the transverse triple score lines, and said gusset sections being adhesively secured to the corresponding underlying outboard gusset panels and portions of said flaps and tabs being adhesively secured to each other whereby all gussets are interiorly folded with closed corners.

6. A bellows-type envelope comprising a blank having an inward side and an outward side, said blank having a first latitudinal score line adapted to provide an outward folding thereof, and two further latitudinal score lines parallel to and equidstant from said first score line, said two further latitudinal score lines being adapted to provide an inward folding of said blank to define a front panel, a back panel and a bottom panel, said bottom panel being disposed between said two further latitudinal score lines, first longitudinal score lines adapted to provide an inward fold and define side panels, and triangular score lines adapted to provide an inward folding of the blank and define two isosceles triangles in each side panel, said triangles being astride said further latitudinal score lines, and two further longitudinal score lines adapted to provide an outward folding of said blank and define flaps coextensive with a portion of each of said panels, each side panel being folded inwardly said outside surface of said triangles having adhesive applied thereto said triangular surfaces being folded into each other to secure same.

7. An envelope as claimed in claim 6, wherein each triangle defined by said score lines includes a base and altitude, said altitude being in registration with the further latitudinal score line that said triangle is astride of, and the base of each triangle being a side edge of said side panel.

8. An envelope as claimed in claim 6, wherein said flaps are coextensive with said side panels defined by said further longitudinal score lines with a portion of said side panel terminating at a point where the triangular score line intersects the side panel.

9. An envelope as claimed in claim 6, wherein said blank includes a cover panel defined by a third latitudinal score line to foldably hinge said cover panel to one of said front and back panels.

10. An envelope as claimed in claim 6, adhesive is disposed on the inward surface of said flaps and said flaps are secured to a portion of the outward surface of the side panel not coextensive therewith. 

1. An end construction for a bellows-type envelope comprising a sheet having an outward and inward surface, a front wall, a bottom wall, and a back wall defined by first inward fold lines on a sheet, side walls defined by second inward fold lines on a sheet, said side walls defining a continuous longitudinal flap on both sides of the front wall, bottom wall and back wall, isosceles triangles defined by third inward fold lines on the side walls, the third inward fold lines being astride the first inward fold lines, and latitudinal extensions coextensive with a portion of each flap and defined by outward longitudinal fold lines, the flaps being folded over respective front, bottom and back walls, the front and back wall folded over in registration with each other and the bottom wall folded outwardly upon itself, the opposing faces on the outward side of each of the triangles being folded together and secured together, the latitudinal extension being secured to said continuous flaps at portions not coextensive with said latitudinal extensions.
 2. The end construction according to claim 1, and a medial outward latitudinal fold line on the bottom wall.
 3. An end construction for a belLows type envelope comprising a sheet having an inward and outward side, three latitudinal fold lines on the sheet, the first and third being inward fold lines defining between them, a bottom for the envelope, and said inward latitudinal fold lines further defining the front and back of the envelope; and the second fold line being an outward fold line defining an outwardly bending fold in the center of the bottom of the envelope, a longitudinal inward fold on each side edge of the sheet extending the length of said sheet, said inward folds defining flaps constituting expandable side walls for the envelope, isosceles triangular areas defined by inward fold lines, each on opposite sides of the second latitudinal fold line, each triangle having an altitude in registration with one of the longitudinal fold lines, each triangle having a base lying on an edge of the flap and a base angle of each triangle terminating on the middle latitudinal fold line at the edge of the flap, each half of one isosceles triangle on one side of the triangles altitude being attached to the opposite half thereof on the other side of the altitude, whereby when the expandable end wall is disposed with the portions on either side of the middle latitudinal fold, in the same plane, the side walls will be extended generally perpendicular to the front and back portions, a latitudinal extension on a portion of the flaps defined by outward longitudinal fold lines, the extensions being attached to the corresponding opposite portion of the flaps.
 4. An expansible envelope comprising: a one piece blank including a substantially rectangular front panel, a back panel coextensive with and hingedly depending from the lower edge of said front panel by inboard and outboard bottom gusset panels defined by transversely extending triple score lines, an inboard gusset panel hinged to each of the lateral edges of said front panel along corresponding inboard longitudinally extending score lines, a gusset section coextensive with and hinged to each of the lateral edges of said back panel along an extension of the corresponding inboard longitudinally extending score line, said inboard and outboard bottom gusset panels, said inboard side gusset panels and said gusset sections all being substantially equal in width along a dimension perpendicular to the respective hinged score lines thereof, a flap substantially coextensive with and hinged to the lower edge of each of said inboard side gusset panels along extensions of the inboard transverse score line and being further hinged to each of the lateral edges of said inboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, a tab substantially coextensive with and hinged to the adjacent edge of each of said gusset sections along extensions of the outboard transverse score line and being further hinged to each of the lateral edges of said outboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, said flaps and said tabs being respectively hinged to each other along extensions of the intermediate transverse score line, a top sealing flap hinged to the upper edge of said front panel, and an outboard side gusset panel hinged to the lateral edge of each of said inboard side gusset panels along a corresponding outboard longitudinally extending score line and having a lower edge terminating at a position short of the inboard transverse score line by a space substantially equal to the width of one of said gusset panels to define a clearance below said outboard side gusset panels, said inboard side gusset panels, said flaps, said tabs and said gusset sections being inwardly folded along the corresponding inboard longitudinally extending score line, said outboard side gusset panels being then outwardly folded along the corresponding outboard longitudinally extending score line, said bottom gusset panels and said back panel being inwardly, outwardly and then inwardly folded along the tranSverse triple score lines, and said gusset sections being adhesively secured to the corresponding underlying outboard gusset panels and portions of said flaps and tabs being adhesively secured to each other whereby all gussets are interiorly folded with closed corners.
 5. An expansible envelope comprising a one piece blank including a substantially rectangular front panel, a back panel coextensive with and hingedly depending from the lower edge of said front panel by inboard and outboard bottom gusset panels defined by transversely extending triple score lines, an inboard side gusset panel hinged to each of the lateral edges of said front panel along corresponding inboard longitudinally extending score lines, a gusset section coextensive with and hinged to each of the lateral edges of said back panel along an extension of the corresponding inboard longitudinally extending score line, said inboard and outboard bottom gusset panels, said inboard side gusset panels and said gusset sections all being substantially equal in width along a dimension perpendicular to the respective hinged score lines thereof, a flap substantially coextensive with and hinged to the lower edge of each of said inboard side gusset panels along extensions of the inboard transverse score line and being further hinged to each of the lateral edges of said inboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, a tab substantially coextensive with and hinged to the adjacent edge of each of said gusset sections along extensions of the outboard transverse score line and being further hinged to each of the lateral edges of said outboard bottom gusset panel along extensions of the corresponding inboard longitudinally extending score line, said flaps and said tabs being respectively hinged to each other along extensions of the intermediate transverse score line, and an outboard side gusset panel hinged to the lateral edge of said inboard side gusset panels along a corresponding outboard longitudinally extending score line and having a lower edge terminating at a position short of the inboard transverse score line by a space substantially equal to the width of one of said gusset panels to define a clearance below said outboard side gusset panels, said inboard side gusset panels, said flaps, said tabs and said gusset sections being inwardly folded along the corresponding inboard longitudinally extending score line, said outboard side gusset panels being then outwardly folded along the corresponding outboard longitudinally extending score line, said bottom gusset panels and said back panel being inwardly, outwardly and then inwardly folded along the transverse triple score lines, and said gusset sections being adhesively secured to the corresponding underlying outboard gusset panels and portions of said flaps and tabs being adhesively secured to each other whereby all gussets are interiorly folded with closed corners.
 6. A bellows-type envelope comprising a blank having an inward side and an outward side, said blank having a first latitudinal score line adapted to provide an outward folding thereof, and two further latitudinal score lines parallel to and equidstant from said first score line, said two further latitudinal score lines being adapted to provide an inward folding of said blank to define a front panel, a back panel and a bottom panel, said bottom panel being disposed between said two further latitudinal score lines, first longitudinal score lines adapted to provide an inward fold and define side panels, and triangular score lines adapted to provide an inward folding of the blank and define two isosceles triangles in each side panel, said triangles being astride said further latitudinal score lines, and two further longitudinal score lines adapted to provide an outward folding of said blank and define flaps coextensive with a portion of each of said panels, each side panel being folded inwardly said outside surface of said triangles having adhesiVe applied thereto said triangular surfaces being folded into each other to secure same.
 7. An envelope as claimed in claim 6, wherein each triangle defined by said score lines includes a base and altitude, said altitude being in registration with the further latitudinal score line that said triangle is astride of, and the base of each triangle being a side edge of said side panel.
 8. An envelope as claimed in claim 6, wherein said flaps are coextensive with said side panels defined by said further longitudinal score lines with a portion of said side panel terminating at a point where the triangular score line intersects the side panel.
 9. An envelope as claimed in claim 6, wherein said blank includes a cover panel defined by a third latitudinal score line to foldably hinge said cover panel to one of said front and back panels.
 10. An envelope as claimed in claim 6, adhesive is disposed on the inward surface of said flaps and said flaps are secured to a portion of the outward surface of the side panel not coextensive therewith. 